C++ :: How To Share Variables Between Two Header Files
Mar 16, 2012Here is what I did,
Code:
// A.h
const int salary = 1000000;
// B.h
extern const int salary = 1000000;
But I still got multi-definition errors. How should I fix it?
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C++ :: How To Change Private Variables In Header Files
Oct 28, 2014How would I change the private variables in the header files and the code in the cpp files for the primary indexes so they use a dynamic array or vector instead. For the primary index, the initial vector size will be 8.
header
#ifndef MY_PRIMARY_INDEX_H
#define MY_PRIMARY_INDEX_H
#include
#include
#include
#include
class PrimaryIndex
[Code] ....
C# :: How To Share Variables Between 3 Classes
Apr 2, 2014I am wondering how to share a variable in 3 classes. For example:
variable class:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
[Code] ...
class that edits the variable:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace ConsoleApplication1
[code]......
The actual program:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace ConsoleApplication1
[code]......
What should happen when this runs is this:
Variable changed in program: 0
Same variable changed in a different class: 1
Instead, this happens:
Variable changed in program: 0
Same variable changed in a different class: 0
Visual C++ :: Should Precompiled Header Files Also Be Included In Source Header Files?
Sep 16, 2013When including a header file in stdafx.h, should that file still be included in the source file where it is actually used?
If it is included in both places, is the one in the source file ignored?
C :: How To Share Imported DLL Functions Between Source Files
Nov 24, 2013In general, my problem is that I've been trying to reorganize the project I and my group are working on into separate project files. Everything was working perfectly fine before, but now I'm facing the wrath of undefined reference errors when I try to call my DLL functions.
I have them declared and included in the central header file here :
Code:
/* DLL functions */
typedef void ( * t_wait )( int milliseconds, const int frames_per_seconds );
typedef clock_t ( * ft_timer )( int command, t_timer * timer_object ); /* clock_t is usually defined as long */
typedef void ( * t_SDL_errorexit )( const char * message );
typedef SDL_Surface * ( * t_load_image )( char * image_path, unsigned is_transparent );
[Code]...
Then I have them imported here :
Code:
/* ******************************************************** */
/* ********* win_error( char *, bool ) ********* */
/* ******************************************************** */
/* - Displays a GUI for a windows specific error message, */
/* pass true to it to have it exit the program, pass false */
/* to have it continue */
/* ******************************************************** */
extern void win_error( char * message, bool is_exit )
{
/* Note : win_error uses the Win32 Api */
/* ********************************** */
char buffer[BUFSIZ] = { 0 }; /*
[code]...
This doesn't work, as my compiler sees it that I am trying to call invalid functions, whereas I have made sure to import the functions before calling. Obviously my compiler can't tell that, and is trying to protect me from calling them.
The source files are compiled as C++, but I'm using C-style code instead of true C++ code.
Obviously I'm using Windows style DLL linking, but if the only ways to share imported functions are non-standard, only post ways that will work on as low as Windows XP.
I have tried to statically link them before, but that led to a problem that I posted a while back. Which led me to dynamically linking, which was problem-free until I separated my code into separate files.
C :: How To Share Variable Value From One Source File To Other Header File
Dec 11, 2014I wanted to share the value of a variable from Sender Program to Receive after program and want to calculate difference between send and receive. After studying Header file concept I program following three.
Now I am struck. How to to compile? I link all these file. I used following method:
Code:
gcc Sender.c -o Sender Sender.h
gcc Receiver.c -o Receiver Student.h
Then I run Sender and after that Receiver.I per my knowledge, Receiver should give difference but it gives error :
Code:
Receiver.c: In function "main":
Receiver.c:10:42: error: "Send" undeclared (first use in this function)
printf(" Total Receive is %d
",Receive-Send);
Code:
Sender.c
#include <stdio.h>
int Send ;
void main(){
[Code] ....
C++ :: Â modifying Several Variables Via Header File
Feb 18, 2014I'm trying to split up my game (about 1300 lines) into header files, but I'm coming up with a problem whenever I try and put a function in a header file, when that function was modifying some variables that were defined before int main in the .cpp. For example:
int variable1 (0);
int variable2 (0);
void increasevariables() {
variable 1 = variable1 + 1;
variable2 = variable2 + 1;
[code].....
If it only modified one variable then I could just pass that variable and the return it:(return variable1 + 1;)But I don't know how to make a function in a header file modify several pre-existing variables. In the actual program, the variables are dependant on each other and the modifying is a lot more complicated, so I'd rather not split it into several functions and run one at a time if there's another way.
C++ :: How Come Header Variables Are Not Recognized In Its CPP File
Feb 24, 2014I declared 3 private variables in header file.
I try to access one of the variable in its corresponding cpp file but I get an error message saying it's undefined. I did #include the header file. Why is this?
C++ :: Create Header File In Which Can Change Value Of Variables
Apr 12, 2013I just can't seem to find how to create a header file and where I can change the value of the variables. It sounds simple.
View 12 Replies View RelatedC++ :: Declare Static Variables In Header File
Oct 15, 2013I read in another forum that it is bad practice to declare static variables in a header file? Is that true and if so why.
View 1 Replies View RelatedC++ :: Header File That Is Continuously Updating To Extract Certain Variables?
Mar 10, 2013I need to write a C++ program, that extracts certain variables, x y z, from a file that is continuously being updated x y z. These variables are going to be used to recalculate a new answer.
My question is to see if it is possible to have an include .h file that is always being updated so that I can extract these three variables from it, and always have the newest venison of each variable, so that the answer to the equation is always the newest updated. Should I use fopen or fwrite to do this.
C :: Header Files Not Found On Mac
Nov 2, 2013I have a piece of code in C with header files included. I run it on Mac OS X Maverick with XCode 4.6.2 installed. GCC is also installed. Note that Command Line Tools in XCode are already installed.
When I compile it, the error I receive says something like this:
add.c:1:19: error: stdio.h: No such file or directory add.c:2:20: error: stdlib.h: No such file or directory add.c:3:20: error: unistd.h: No such file or directory
However when I run it on Ubuntu, it compiles without a problem.What to do?
C++ :: Using Namespaces In Header Files
Dec 9, 2013So I've been making a header file and put variables in their own namespace to avoid conflicts. My question is, do functions in the header file normally go in a namespace too, or should they just be named in a way which makes them unlikely to be accidentally copied?
View 15 Replies View RelatedC++ :: Precompiled Header Files
Apr 2, 2013My teacher talks about header files just having definitions and not declerations. I am writing a program that has a .h file and a related .cpp file along with a main.cpp it would be nice to have the .cpp file associated with the .h file compiled into an object file that would than just be referenced when the .h file is included. Am I making any sense?
View 2 Replies View RelatedC++ :: How To Use Two Header Files In Program
Sep 17, 2013I want to use two header files in my program. Here is exactly what I want to do.
-In the first header I have a binary tree and a structure.
-In the second file I have another functions that need to use the structure in the first header.
-I also want to use a function from the second header in the first.
-And finally I want to do actions with both headers in a "main.cpp" file that contains only int main() function.
How to include the headers in each other and in the main.cpp to be able to do the actions above?
I try to include the first header in the second one and the second one in the first header. Then I include both headers in the main.cpp file. But the compiler shows me many errors.
C++ :: Two Header Files - How To Use Namespace
May 2, 2013I have two header files, A, B.
A.h
namespace test {
struct info
{
int a;
}
}
B.h
#include "A.h"
int main {
test::info.a = 10;
}
However, it has an error. I don't quite understand how to use namespace.
C++ :: Finding Nested Header Files?
Aug 27, 2013I'm working with CGAL - Computational Geometry Algorithms Library, which is a library of geometry functions declared as several thousand header-only files. When I run a basic program (source code [URL] ) I get this output: [URL]
I have tried switching angle brackets to quotes. I have also started reading up on CMake.
Do I need to walk the dependency tree and add all of those files to my CMakeLists.txt? Or is there a way to tell the compiler to look in subdirectories?
C :: How To Deal With Conflicts In Header Files
Nov 6, 2013I have some header files with generic functions. And in one of them, I define TRUE and FALSE. Recently I started using another header file and it defined TRUE and FALSE as well. That caused GCC to throw an error, and not compile. In my case I can put #IFNDEF around the values so that if it is already defined they don't get defined again, but is there a better way to handle duplicate names? I assume the case would be the same for duplicated functions, how does that get handled?
View 6 Replies View RelatedC :: Making Header Files With Extension?
Mar 6, 2015I have a problem with making header files in c, i get the code written only in main.c and then i have to create a files with extension .h and extension .c but how to do it.
View 4 Replies View RelatedC++ :: Using A Header File Across Multiple Files?
Aug 2, 2014So say I create a header file which contains a list of structs, and I want to use these structs through out my source and some of my classes... how would I accomplish this?
When I try to do it via #include, I get re-definition errors, due to the nature of #pragma once. If I switch to #ifndef then I lack defenitions in files other than the source.
Is there a way to define things such as structs across multiple files, which doesn't lead to re-definition errors, and doesn't involve manually re-created all the structs for each file?
C++ :: How To Make Header Files Work
Dec 3, 2013I'm having with header files, specifically to do with the string data type. The objects work perfectly when I put them inside the .cpp but when I set it to include the exact same code in a .h, I get a string of error messages.
class Topic
{
private:
string NInfo, SInfo, EInfo, WInfo, Name ;
bool Quest ;
[code]....
C++ :: Where Is The Path For Header Files For Mac Xcode
May 27, 2013I want to include turboc.h file for some project
where do i have to add this file for mac xcode?
C++ :: Default Constructors And Header Files?
Jun 8, 2013I'm working on trying to figure out constructors and header files. Can ya'll help me out with this? I'm sure my code looks like a mess as I tried to piece together different solutions I've found. There's also an attempted copy constructor and operator function. Basically my problem is my source file says there is no default constructor for my class type. Here's my header code:
#include <iostream>
#ifndef _car
#define _car
[Code].....
C++ :: Creating Header Files With Functions
Oct 30, 2014I currently have a running program "game.cpp" that runs a game of tic tack toe. I want to split the working functions into header files so that game.cpp isn't so cluttered. I have created two header files "displayBoard.h" and "gamePlay.h" but they wont compile because the functions are looking for variables that haven't been declared. First, here's the working code.
#include "displayBoard.h"
#include <iostream>
#include <limits> //This is required to catch invalid user input
class ticTacToe //A class to contain all our functions {
[Code] .....
C/C++ :: Linking Classes Through Header Files?
Jul 30, 2014I am having the issue of trying to call functions of a class through the header file.
Test.h
#ifndef TEST_H
#define TEST_H
class Test {
public:
void Hello();
[code]....
This code returns the error "undefined reference to 'Test::Hello()'"
All I am trying to do is call the Hello(); function in a seperate file.
C/C++ :: How To Compile Two CPP Files With Header File
Jan 28, 2015this is my main cpp file:
#include<iostream>
#include<conio.h>
#include "C:UsersAmitDesktopNew foldersum.h"
using namespace std;
int main() {
int a;
int b;
[Code]...
this is my 2nd cpp file add two number
#include<iostream>
#include "C:UsersAmitDesktopNew foldersum.h"
int sum(int x,int y) {
return(x+y);
}
this is my header file used in both cpp file
#ifndef SUM_H
#def SUM_H
int sum(int x,int y);
#endif
error i am getting in main cpp in devc++
[Linker error] undefined reference to `sum(int, int)'
[Linker error] undefined reference to `sum(int, int)'
in 2nd cpp file [Linker error] undefined reference to `WinMain@16' [/code]